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OK fellas, the time is drawing near. I've got a spare car for the first two weeks of the year. I think I'm going to take the heads off of the truck and and get a valve job while I can live without it. (I know I've got at least one bad valve...)
79 F150 351M 4x4 automatic. I'm pretty certain that I'll have to remove the heater/AC blower from the firewall...what else do I need to know? Anyone done this recently?
A friends Dad told me to loosen the intake bolts, exhaust manifold bolts, and the head bolts, then turn the engine over a few times to use the cylinder compression to help break the seals. Sound good? Or does it sound like a fire waiting to happen?
Actually, if you run the carb dry, either by pinching or disconnecting the lines, and then remove the coil wire, you should be fine. Keep it mind that you'll need to have drained the coolant, otherwise you'll have a mess. You may also want to be very careful as you could bend a push rod or something. Then again, push rods are cheap, so your choice...
Sounds like a neat idea. Never thought of turning it over to break seals. Although, to avoid bending the pushrods, you could use compressed air through a spark plug hole and take the pushrods out. Also, I have never found heads to be very difficult to remove. just a gental pry with a hammer handle through the intake port will break the head free.
may as well do a new intake gasket while your there just for insurance. on my 400 i took the whole top end off and the heads i pried o nthe front edge with a flat head screwdriver there is a little notch in my heads atleast for it to fit.
and then just lifted em off man are they heavy!!!!!!
Do 351M's and 400's have mammoth combustion chambers or dished pistons? both? I know they are really low compression engines, also are the 351M and 400 heads copies of the 351 Cleveland's?
Just so you know, you do not have to touch the AC shroud on the firewall. Yoy can leave it there. I did and I have a 460 ford. I will say though, it would have been nice to have some extra room.
[QUOTE=tcbofade] ...A friends Dad told me to loosen the intake bolts, exhaust manifold bolts, and the head bolts, then turn the engine over a few times to use the cylinder compression to help break the seals... QUOTE]
the old trick i heard was to remove all the pushrods and all but 1 slightly loosened head bolt for safety, then turn the engine over to crack the head gaskets loose. i don't see how the intake or exhaust manifolds would be affected though? i've used the method a few times.
you can leave the exhaust manifolds connected to the heads and pull them out together if you disconnect the pipes from the manifolds. it's a little heavier but allows you to work on the X manifold bolts on the bench or floor where you can get a good grab on them. the shop tech won't appreciate it much but the valve job could even be done with the manifolds still attached if need be, but i don't see why you wouldn't be able to get 'em off.
Last edited by grclark351; Dec 26, 2006 at 12:59 AM.